Deck 19: The Atom

Question 1

What is the kinetic energy of ejected electrons from a silver surface with work function E_A = 4.73 eV if it is illuminated with light at a frequency of f = 2.28 × 10¹⁵ Hz? [h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

A)0.38 eV
B)4.72 eV
C)9.40 eV
D)15.1 eV

Answer 1

4.72 eV

Question 2

What is the ionization energy of a hydrogen atom? [h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

A)0.8 eV
B)1.5 eV
C)3.4 eV
D)13.6 eV

Answer 2

13.6 eV

Question 3

What is the critical wavelength of an incoming light that ejects electrons from a metal whose work function is E_A = 5.02 eV? [h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

A)39 nm
B)64 nm
C)120 nm
D)250 nm

Answer 3

250 nm

Question 4

What is the critical frequency of an incoming light that ejects electrons from a metal whose work function is E_A = 5.02 eV? [h = 6.63 × 10^-34 J s, 1 eV = 1.6 × 10^-19 J]

A)1.2 × 10¹⁵ Hz
B)2.5 × 10¹⁵ Hz
C)4.7 × 10¹⁵ Hz
D)7.6 × 10¹⁵ Hz

Question 5

Which of the following occurs when an electron transitions from a lower orbit to a higher one?

A)The atom emits a photon.
B)The atom absorbs a photon.
C)The atom releases energy.
D)No changes occur.

Question 6

What is the longest wavelength of photon emitted during the transition of an electron in a hydrogen atom in the Bracket series? [R_H = 3.29 × 10¹⁵ Hz]

A)1460 nm
B)1820 nm
C)1940 nm
D)4050 nm

Question 7

What is the highest frequency of photon emitted during the transition of an electron in a hydrogen atom in the Bracket series? [R_H = 3.29 × 10¹⁵ Hz]

A)0.7 × 10¹⁴ Hz
B)1.6 × 10¹⁴ Hz
C)1.7 × 10¹⁴ Hz
D)2.1 × 10¹⁴ Hz

Question 8

What does the number of electrons emitted in the photoelectric effect depend on?

A)the frequency of the incident light
B)the energy of the incident light
C)the intensity of the incident light
D)the wavelength of the incident light

Question 9

What does the kinetic energy of electrons emitted in the photoelectric effect depend on?

A)the frequency of the incident light
B)the number of photons in the incident light
C)the intensity of the incident light
D)the amplitude of the incident light

Question 10

Which of these events happens when an electron transitions from the n = 2 to the n = 4 level in a hydrogen atom?

A)A photon of frequency f = 6.19 × 10¹⁴ Hz is emitted.
B)A photon of frequency f = 6.19 × 10¹⁴ Hz is absorbed.
C)A photon of frequency f = 3.08 × 10¹⁵ Hz is emitted.
D)A photon of frequency f = 3.08 × 10¹⁵ Hz is absorbed.

Question 11

Which of these scientists discovered the electron?

A)J.J.Thomson
B)Ernest Rutherford
C)Isaac Newton
D)James Maxwell

Question 12

Imagine an atom as a sphere volume. What would make up most of the volume of the sphere?

A)electrons
B)nucleus
C)empty space
D)The volume is divided roughly in thirds between the electron cloud, the nucleus, and the empty space between the electrons and the nucleus.

Question 13

What is the kinetic energy of the electron equal to if it is ejected from a metal with a work function equal to the energy of an incoming photon?

A)zero
B)the work function
C)the incident photon energy
D)the nature of the material

Question 14

If an electron within an atom has space that is limited by the size of the atom (10^-10 m), what is the minimum uncertainty in its momentum? [h = 6.63 × 10^-34 J s]

A)0.52 × 10^-24 kg m/s
B)1.05 × 10^-24 kg m/s
C)3.31 × 10^-24 kg m/s
D)6.63 × 10^-24 kg m/s

Question 15

Why don't we see macroscopic objects behave like waves?

A)Their wavelength is too large to observe.
B)Their wavelength is too small to observe.
C)Their motion is too slow to observe wavelike properties.
D)Macroscopic objects are not waves.

Question 16

Which of the following occurs when an electron transitions from a higher orbit to a lower one?

A)The atom emits a photon.
B)The atom absorbs a photon.
C)The atom absorbs energy.
D)No changes occur.

Question 17

Which of these statements accurately describes how the energy of an electron in the third orbit in a helium atom differs from the total energy of an electron in the third orbit in a hydrogen atom?

A)The energy of the electron in the third orbit in the helium atom is 2 times greater than the energy of the electron in the hydrogen atom.
B)The energy of the electron in the third orbit in the helium atom is 4 times greater than the energy of the electron in the hydrogen atom.
C)The energy of the electron in the third orbit in the helium atom is half the energy of the electron in the hydrogen atom.
D)The energy of the electron in the third orbit in the helium atom is one-quarter the energy of the electron in the hydrogen atom.

Question 18

What is the work function, E_A, of a metal from which electrons are ejected with kinetic energy E_kin = 0.5 eV, and the incident light has a wavelength of ë = 460 nm? [h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

A)1.7 eV
B)2.2 eV
C)4.2 eV
D)4.7 eV

Question 19

What is the kinetic energy of ejected electrons from a silver surface with a work function of E_A = 4.73 eV if the silver is illuminated with light at a wavelength of ë = 144.2 nm? [h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

A)3.89 eV
B)4.73 eV
C)8.62 eV
D)13.4 eV

Question 20

What is the ratio of the de Broglie wavelength for an electron (m_e = 9.1 × 10^-31 kg) moving at a speed of 1.70 × 10⁴ m/s and a ball of a mass = 0.5 kg moving at a speed of 13 m/s? [h = 6.63 × 10^-34 Js]

A)1.1 × 10²⁷
B)1.4 × 10²⁵
C)1.3 × 10^-28
D)1.3 × 10^-38

Question 21

Which transition of the electron in a hydrogen atom results in emission of the highest frequency in the Balmer series? Calculate the frequency.
[R_H = 3.29 × 10¹⁵ Hz]

Question 22

What is the kinetic energy of an electron ejected from a sodium surface, whose work function is E_A = 2.28 eV, when it is illuminated with light of wavelength ë = 380 nm?
[h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

Question 23

What is the work function of a metal from which electrons are ejected with kinetic energy E_kin = 1.88 eV, and incident light has a wavelength of ë = 660 nm?
[h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

Question 24

When an electron transfers between levels in an atom, the wavelength of an emitted or absorbed photon depends only on the energy of the level from which the electron transfers.

Question 25

What is kinetic energy of an electron ejected from a sodium surface, whose work function is E_A = 2.28 eV, when it is illuminated with light of frequency f = 1.88 × 10¹⁵ Hz?
[h = 6.63 × 10^-34 J s, c = 3 × 10⁸ m/s, 1 eV = 1.6 × 10^-19 J]

Question 26

Which transition of the electron in a hydrogen atom results in emission of the longest wavelength in the Paschen series? Calculate the wavelength.
[R_H = 3.29 × 10¹⁵ Hz, c = 3 × 10⁸ m/s]

Question 27

What is the critical wavelength of an incoming light that ejects electrons from a metal whose work function is E_A= 4.7 eV?

Question 28

Which transition of the electron in a hydrogen atom results in emission of the lowest frequency in the Lyman series? Calculate the frequency.
[R_H = 3.29 × 10¹⁵ Hz]

Question 29

What is the de Broglie wavelength for an electron (m_e = 9.1 × 10^-31 kg) moving at a speed of 3.0 × 10⁶ m/s, and a ball of mass = 0.45 kg, moving at a speed of 13 m/s?

Question 30

The majority of the mass in the atom is concentrated in its electrons.

Question 31

What is the critical frequency of an incoming light that ejects electrons from a metal whose work function is E_A = 4.7 eV?

Question 32

The majority of the volume of an atom is empty space.

Question 33

Net force causing circular uniform motion is along the path.

Question 34

Because of the large mass of a 2 kg ball compared to an electron (m_e = 9.1 × 10^-31 kg), we know at the same time the position and velocity of the ball with very small uncertainty, as opposed to an electron, for which the uncertainty in knowing the velocity is very large if we know its position.

Question 35

The total energy of an electron in the second level (quantum number n = 2) is 2 times higher than the energy on the ground level (n = 1).

Question 36

An electron loses energy when it transfers from the higher energy level to a lower level.

Question 37

Electrons do NOT lose energy via radiation when they circle the atomic nucleus.

Question 38

Wave-particle dualism implies that electrons and other atomic size particles are behaving as waves and particles at the same time.

Question 39

Which transition of the electron in a hydrogen atom results in absorption of the shortest wavelength in the Lyman series? Calculate the wavelength.
[R_H = 3.29 × 10¹⁵ Hz, c = 3 × 10⁸ m/s]

Question 40

Work function is the energy with which the electron moves out of the metal in the photoelectric effect.